The customs' data showed that during the first six months, trade with the European Union jumped 17.4 percent year on year.

A Chinese government official said Thursday that China-North Korea trade was worth $2.6 billion in the first half of 2017, up about 10% over the same period a year ago.

China announced in February the suspension of coal imports from the North, striking a blow at a major source of income for the hermit state.

While Beijing is North Korea's longtime ally in the region, the state has voiced frustration with North Korean leader Kim Jong Un's aggressive behavior.

The growth bilateral trade "should not be used as basis for questioning China's solemn attitude towards the implementation of the Security Council's resolutions", Huang Songping, a spokesman for Chinese Customs, told reporters in Beijing.

"UN Security Council sanctions are not a total ban on shipments".

China, the world's largest coal buyer, imported 21.6 million tonnes of coal in June, down from a month ago, preliminary customs data showed on Thursday.

China's defense of the trades comes after Trump has repeatedly pressed Chinese President Xi Jinping about adding additional pressure to stop the North's pursuit of a nuclear weapon.

Huang said the price fluctuation of commodities could also potentially boost the trade figure as measured by value.

Last week US President Donald Trump denounced China's trade with North Korea, saying it had grown nearly 40 percent in the first quarter, and cast doubt on whether Beijing was helping to counter the threat from North Korea.

Completing a hat-trick of beats, the national trade surplus grew from $40.81 billion to $42.77 billion, marginally topping the $42.44 billion level expected.

As the United States has searched for ways to punish North Korea for its repeated defiance of global bans on it testing nuclear weapons and launching ballistic missiles, it has repeatedly turned to China. Imports have fallen since March, when they declined 36.5 percent, he said. "So much for China working with us - but we had to give it a try", Trump said in tweet last week.